It has become commonplace in homes, commercial buildings and industrial establishments to compact trash and waste for conserving space and in retail business establishments for saving labor costs. For example, commercial establishments, such as fast food restaurants and the like, have peak hours when there is a need to dispose of large amounts of highly compactable waste such as disposable cups, dishes, eating utensils and food. When such trash or waste is not compacted, large disposal areas or frequent waste removal is required, particularly at a time when personnel are the busiest.
Trash or waste containers are typically made in standard sizes for use in the waste bins of commercial establishments. Such waste bins are normally provided at their lower portions with a door or drawer for access to remove or replace the containers when they are full. At their upper ends, the containers usually have an opening for depositing trash. The opening can be provided with a hinged closure member, which, if manually opened by the user, often causes problems. In particular, a user or customer carrying a full tray of trash to be disposed of is required to manually push open the closure member or door while holding the trash and, in so doing, runs the risk of dropping trash on the floor which is clearly undesirable and can also create a hazard.
Typical of prior art waste or trash compactors is the compactor disclosed in U.S. Pat. No. 3,901,139. Each time the door is opened to introduce trash, the time interval is registered. When the total time of successive openings exceeds a predetermined setting, the compactor member is operated through one cycle. Although the compactor is not operated each time the door is opened, it can operate while the door is open. A safety shield is provided inside the compactor to prevent the hand of the user from moving into the path of the compactor member, but the possibility of accidents occuring, for example, when the shield is not properly positioned, still remain.
Other patents of interest which relate to trash compactors include U.S. Pat. Nos. 3,155,314 and 3,081,937 to Kreider. These patents describe trash disposal systems which use pneumatic control mechanisms to open and close the access members to the trash disposal system. U.S. Pat. No. 3,003,317 to Schroeder et al and U.S. Pat. No. 2,843,376 to Osuch et al disclose systems using sensors to open and close trash access doors. U.S. Pat. Nos. 3,212,433 and 3,212,432 to Raab disclose an electric eye and time relay system to activate a compacting ram after sufficient material has been accumulated for baling.
U.S. Pat. No. 3,905,289 to Engebretsen discloses a compactor that includes a compaction receptacle and a separate compartment disposed above the receptacle to permit materials to be deposited in the compactor without moving the entire receptacle out of the compactor housing. U.S. Pat. No. 4,044,642 to Budoff discloses a system for handling of solid waste which includes a door that provides access to a compactor unit, the door being automatically opened or closed in response to the presence or absence of a motor vehicle.
What is desired is to provide a waste compactor suitable for installation in conventional existing waste containers, particularly in commercial establishments, wherein the trash access door opens automatically as the customer or user approaches, thus enabling the user to have both hands free to dispose of the waste products. For safety reasons, it is desired, on the one hand, that the compactor member be inoperative as long as the trash access door is open, and on the other hand, that the trash access door be securely locked once the compaction cycle is initiated to prevent accidents from occurring. In addition, it is desirable to provide a self-contained trash compactor unit that can easily fit or slide into standard trash containers of existing size and configuration so that the unit can be retrofitted and removed from the waste systems on site.